Well, this problem can be solved easily using recursion: just find the closest value in theleftandrightsubtrees and compare them withroot -> val. The code is as follows. 1classSolution {2public:3intclosestValue(TreeNode* root,doubletarget) {4if(!root)returnINT_MAX;5if(!(root -> left)...
Problem Given a binary tree, determine if it is a valid binary search tree (BST). Assume a BST is defined as follows: The left subtree of a node contains only nodes with keys less than the node's key. The right subtree of a node contains only nodes with keys greater than the node'...
Given the root node of a binary search tree (BST) and a value. You need to find the node in the BST that the node's value equals the given value. Return the subtree rooted with that node. If such node doesn't exist, you should return NULL. For example, Given the tree: 4 / \ ...
-105<= Node.val <= 105 Follow up:Could you do that without using any extra space? (Assume that the implicit stack space incurred due to recursion does not count). Copyright ©️ 2025 LeetCode All rights reserved Case 1 Case 2 [1,null,2,2]...
Follow up:Could you do that without using any extra space? (Assume that the implicit stack space incurred due to recursion does not count). 粗暴解法,直接hash计数然后找出最大计数的值。 # Definition for a binary tree node. # class TreeNode(object): ...
Follow up: Could you do that without using any extra space? (Assume that the implicit stack space incurred due to recursion does not count). 这道题让我们求二分搜索树中的众数,这里定义的二分搜索树中左根右结点之间的关系是小于等于的,有些题目中是严格小于的,所以一定要看清题目要求。所谓的众数就...
LeetCode "Binary Tree Upside Down" Recursion, a natural thought: classSolution {//Top : BottomRightstd::pair<TreeNode *, TreeNode *> rotate(TreeNode *p) {if(!p->left && !p->right) {returnmake_pair(p, p); } auto r= rotate(p->left);...
The time complexity of deletion in a binary search tree using lazy deletion and recursion is O(h), where h is the height of the tree. The worst-case scenario is when the tree is completely unbalanced, where the height of the tree is equal to the number of nodes in the tree. In this...
How to code Binary Search Algorithm using Recursion in Java? Example How to convert Decimal to Binary Number in Java? Example Tutorial Counting Sort in Java - Example How to check if an array contains a number in Java? How to sort an array in place using the QuickSort algorithm? How do...
102. 二叉树的层序遍历 - 给你二叉树的根节点 root ,返回其节点值的 层序遍历 。 (即逐层地,从左到右访问所有节点)。 示例 1: [https://assets.leetcode.com/uploads/2021/02/19/tree1.jpg] 输入:root = [3,9,20,null,null,15,7] 输出:[[3],[9,20],[15,7]]